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controlling terminal is a vnode
[unix-history] / usr / src / sys / kern / tty_pty.c
/*
* Copyright (c) 1982, 1986, 1989 The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by the University of California, Berkeley. The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*
* @(#)tty_pty.c 7.9 (Berkeley) %G%
*/
/*
* Pseudo-teletype Driver
* (Actually two drivers, requiring two entries in 'cdevsw')
*/
#include "pty.h"
#if NPTY > 0
#include "param.h"
#include "systm.h"
#include "ioctl.h"
#include "tty.h"
#include "user.h"
#include "conf.h"
#include "file.h"
#include "proc.h"
#include "uio.h"
#include "kernel.h"
#include "vnode.h"
#include "tsleep.h"
#if NPTY == 1
#undef NPTY
#define NPTY 32 /* crude XXX */
#endif
#define BUFSIZ 100 /* Chunk size iomoved to/from user */
/*
* pts == /dev/tty[pqrs]?
* ptc == /dev/pty[pqrs]?
*/
struct tty pt_tty[NPTY];
struct pt_ioctl {
int pt_flags;
struct proc *pt_selr, *pt_selw;
u_char pt_send;
u_char pt_ucntl;
struct clist pt_ioc;
} pt_ioctl[NPTY];
int npty = NPTY; /* for pstat -t */
int ptydebug = 0;
#define PF_RCOLL 0x0001
#define PF_WCOLL 0x0002
#define PF_NBIO 0x0004
#define PF_PKT 0x0008 /* packet mode */
#define PF_STOPPED 0x0010 /* user told stopped */
#define PF_REMOTE 0x0020 /* remote and flow controlled input */
#define PF_NOSTOP 0x0040
#define PF_UCNTL 0x0080 /* user control mode */
#define PF_TIOC 0x0100 /* transparent control mode */
#define PF_LIOC 0x0200 /* transparent control locked */
#define PF_WIOC 0x0400 /* waiting for PF_LIOC to clear */
#define PF_BLOCK 0x0800 /* block writes to slave */
#define PF_OWAIT 0x1000 /* waiting for PF_BLOCK to clear */
/*ARGSUSED*/
ptsopen(dev, flag)
dev_t dev;
{
register struct tty *tp;
int error;
#ifdef lint
npty = npty;
#endif
if (minor(dev) >= NPTY)
return (ENXIO);
tp = &pt_tty[minor(dev)];
if ((tp->t_state & TS_ISOPEN) == 0) {
ttychars(tp); /* Set up default chars */
tp->t_iflag = TTYDEF_IFLAG;
tp->t_oflag = TTYDEF_OFLAG;
tp->t_lflag = TTYDEF_LFLAG;
tp->t_cflag = TTYDEF_CFLAG;
tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED;
ttsetwater(tp); /* would be done in xxparam() */
} else if (tp->t_state&TS_XCLUDE && u.u_uid != 0)
return (EBUSY);
if (tp->t_oproc) /* Ctrlr still around. */
tp->t_state |= TS_CARR_ON;
while ((tp->t_state & TS_CARR_ON) == 0) {
tp->t_state |= TS_WOPEN;
if (flag&FNDELAY)
break;
sleep((caddr_t)&tp->t_rawq, TTIPRI);
}
error = (*linesw[tp->t_line].l_open)(dev, tp, flag);
ptcwakeup(tp, FREAD|FWRITE);
return (error);
}
ptsclose(dev)
dev_t dev;
{
register struct tty *tp;
tp = &pt_tty[minor(dev)];
(*linesw[tp->t_line].l_close)(tp);
ttyclose(tp);
ptcwakeup(tp, FREAD|FWRITE);
return (0);
}
ptsread(dev, uio, flag)
dev_t dev;
struct uio *uio;
{
register struct tty *tp = &pt_tty[minor(dev)];
register struct pt_ioctl *pti = &pt_ioctl[minor(dev)];
int error = 0;
again:
if (pti->pt_flags & PF_REMOTE) {
while (isbackground(u.u_procp, tp)) {
if ((u.u_procp->p_sigignore & sigmask(SIGTTIN)) ||
(u.u_procp->p_sigmask & sigmask(SIGTTIN)) ||
u.u_procp->p_pgrp->pg_jobc == 0 ||
u.u_procp->p_flag&SVFORK)
return (EIO);
pgsignal(u.u_procp->p_pgrp, SIGTTIN);
sleep((caddr_t)&lbolt, TTIPRI);
}
if (tp->t_canq.c_cc == 0) {
if (flag & IO_NDELAY)
return (EWOULDBLOCK);
sleep((caddr_t)&tp->t_canq, TTIPRI);
goto again;
}
while (tp->t_canq.c_cc > 1 && uio->uio_resid > 0)
if (ureadc(getc(&tp->t_canq), uio) < 0) {
error = EFAULT;
break;
}
if (tp->t_canq.c_cc == 1)
(void) getc(&tp->t_canq);
if (tp->t_canq.c_cc)
return (error);
} else
if (tp->t_oproc)
error = (*linesw[tp->t_line].l_read)(tp, uio, flag);
ptcwakeup(tp, FWRITE);
return (error);
}
/*
* Write to pseudo-tty.
* Wakeups of controlling tty will happen
* indirectly, when tty driver calls ptsstart.
*/
ptswrite(dev, uio, flag)
dev_t dev;
struct uio *uio;
{
register struct tty *tp = &pt_tty[minor(dev)];
register struct pt_ioctl *pti = &pt_ioctl[minor(dev)];
if (tp->t_oproc == 0)
return (EIO);
while (pti->pt_flags & PF_BLOCK) {
pti->pt_flags |= PF_OWAIT;
sleep((caddr_t)pti + 1, TTOPRI);
}
return ((*linesw[tp->t_line].l_write)(tp, uio, flag));
}
/*
* Start output on pseudo-tty.
* Wake up process selecting or sleeping for input from controlling tty.
*/
ptsstart(tp)
struct tty *tp;
{
register struct pt_ioctl *pti = &pt_ioctl[minor(tp->t_dev)];
if (tp->t_state & TS_TTSTOP)
return;
if (pti->pt_flags & PF_STOPPED) {
pti->pt_flags &= ~PF_STOPPED;
pti->pt_send = TIOCPKT_START;
}
ptcwakeup(tp, FREAD);
}
ptcwakeup(tp, flag)
struct tty *tp;
{
struct pt_ioctl *pti = &pt_ioctl[minor(tp->t_dev)];
if (flag & FREAD) {
if (pti->pt_selr) {
selwakeup(pti->pt_selr, pti->pt_flags & PF_RCOLL);
pti->pt_selr = 0;
pti->pt_flags &= ~PF_RCOLL;
}
wakeup((caddr_t)&tp->t_outq.c_cf);
}
if (flag & FWRITE) {
if (pti->pt_selw) {
selwakeup(pti->pt_selw, pti->pt_flags & PF_WCOLL);
pti->pt_selw = 0;
pti->pt_flags &= ~PF_WCOLL;
}
if (ptydebug) printf("WAKEUP c_cf %d\n", u.u_procp->p_pid);
wakeup((caddr_t)&tp->t_rawq.c_cf);
}
}
/*ARGSUSED*/
ptcopen(dev, flag)
dev_t dev;
int flag;
{
register struct tty *tp;
struct pt_ioctl *pti;
if (minor(dev) >= NPTY)
return (ENXIO);
tp = &pt_tty[minor(dev)];
if (tp->t_oproc)
return (EIO);
tp->t_oproc = ptsstart;
(void)(*linesw[tp->t_line].l_modem)(tp, 1);
pti = &pt_ioctl[minor(dev)];
pti->pt_flags = 0;
pti->pt_send = 0;
pti->pt_ucntl = 0;
return (0);
}
ptcclose(dev)
dev_t dev;
{
register struct tty *tp;
tp = &pt_tty[minor(dev)];
(void)(*linesw[tp->t_line].l_modem)(tp, 0);
tp->t_state &= ~TS_CARR_ON;
tp->t_oproc = 0; /* mark closed */
tp->t_session = 0;
return (0);
}
ptcread(dev, uio, flag)
dev_t dev;
struct uio *uio;
{
register struct tty *tp = &pt_tty[minor(dev)];
struct pt_ioctl *pti = &pt_ioctl[minor(dev)];
char buf[BUFSIZ];
int error = 0, cc;
/*
* We want to block until the slave
* is open, and there's something to read;
* but if we lost the slave or we're NBIO,
* then return the appropriate error instead.
*/
for (;;) {
if (tp->t_state&TS_ISOPEN) {
if (pti->pt_flags&PF_PKT && pti->pt_send) {
error = ureadc((int)pti->pt_send, uio);
if (error)
return (error);
pti->pt_send = 0;
return (0);
}
if (pti->pt_flags&PF_UCNTL && pti->pt_ucntl) {
error = ureadc((int)pti->pt_ucntl, uio);
if (error)
return (error);
pti->pt_ucntl = 0;
return (0);
}
if (pti->pt_flags&PF_TIOC && pti->pt_ioc.c_cc) {
if (uio->uio_resid < pti->pt_ioc.c_cc + 1)
return (E2BIG);
error = ureadc(TIOCPKT_TIOC, uio);
while (error == 0 && pti->pt_ioc.c_cc > 0) {
cc = q_to_b(&pti->pt_ioc, buf,
MIN(pti->pt_ioc.c_cc, BUFSIZ));
if (cc <= 0) /* impossible? */
break;
error = uiomove(buf, cc, UIO_READ, uio);
}
return (error);
}
if (tp->t_outq.c_cc && (tp->t_state&TS_TTSTOP) == 0)
break;
}
if ((tp->t_state&TS_CARR_ON) == 0)
return (0); /* EOF */
if (flag & IO_NDELAY)
return (EWOULDBLOCK);
if (ptydebug) printf("SLEEP(1) c_cf %d\n", u.u_procp->p_pid);
sleep((caddr_t)&tp->t_outq.c_cf, TTIPRI);
}
if (pti->pt_flags & (PF_PKT|PF_UCNTL|PF_TIOC))
error = ureadc(0, uio);
while (uio->uio_resid > 0 && error == 0) {
cc = q_to_b(&tp->t_outq, buf, MIN(uio->uio_resid, BUFSIZ));
if (cc <= 0)
break;
error = uiomove(buf, cc, uio);
}
if (tp->t_outq.c_cc <= TTLOWAT(tp) && !(pti->pt_flags & PF_BLOCK))
ptswake(tp);
return (error);
}
ptswake(tp)
register struct tty *tp;
{
if (tp->t_state&TS_ASLEEP) {
tp->t_state &= ~TS_ASLEEP;
wakeup((caddr_t)&tp->t_outq);
}
if (tp->t_wsel) {
selwakeup(tp->t_wsel, tp->t_state & TS_WCOLL);
tp->t_wsel = 0;
tp->t_state &= ~TS_WCOLL;
}
}
ptsstop(tp, flush)
register struct tty *tp;
int flush;
{
struct pt_ioctl *pti = &pt_ioctl[minor(tp->t_dev)];
int flag;
/* note: FLUSHREAD and FLUSHWRITE already ok */
if (flush == 0) {
flush = TIOCPKT_STOP;
pti->pt_flags |= PF_STOPPED;
} else
pti->pt_flags &= ~PF_STOPPED;
pti->pt_send |= flush;
/* change of perspective */
flag = 0;
if (flush & FREAD)
flag |= FWRITE;
if (flush & FWRITE)
flag |= FREAD;
ptcwakeup(tp, flag);
}
ptcselect(dev, rw)
dev_t dev;
int rw;
{
register struct tty *tp = &pt_tty[minor(dev)];
struct pt_ioctl *pti = &pt_ioctl[minor(dev)];
struct proc *p;
int s;
if ((tp->t_state&TS_CARR_ON) == 0)
return (1);
switch (rw) {
case FREAD:
/*
* Need to block timeouts (ttrstart).
*/
s = spltty();
if ((tp->t_state&TS_ISOPEN) &&
tp->t_outq.c_cc && (tp->t_state&TS_TTSTOP) == 0) {
splx(s);
return (1);
}
splx(s);
/* FALLTHROUGH */
case 0: /* exceptional */
if ((tp->t_state&TS_ISOPEN) &&
(pti->pt_flags&PF_PKT && pti->pt_send ||
pti->pt_flags&PF_TIOC && pti->pt_ioc.c_cc ||
pti->pt_flags&PF_UCNTL && pti->pt_ucntl))
return (1);
if ((p = pti->pt_selr) && p->p_wchan == (caddr_t)&selwait)
pti->pt_flags |= PF_RCOLL;
else
pti->pt_selr = u.u_procp;
break;
case FWRITE:
if (tp->t_state&TS_ISOPEN) {
if (pti->pt_flags & PF_REMOTE) {
if (tp->t_canq.c_cc == 0)
return (1);
} else {
if (tp->t_rawq.c_cc + tp->t_canq.c_cc < TTYHOG-2)
return (1);
if (tp->t_canq.c_cc == 0 && (tp->t_iflag&ICANON))
return (1);
}
}
if ((p = pti->pt_selw) && p->p_wchan == (caddr_t)&selwait)
pti->pt_flags |= PF_WCOLL;
else
pti->pt_selw = u.u_procp;
break;
}
return (0);
}
ptcwrite(dev, uio, flag)
dev_t dev;
register struct uio *uio;
{
register struct tty *tp = &pt_tty[minor(dev)];
register struct iovec *iov;
register char *cp;
register int cc = 0;
char locbuf[BUFSIZ];
int cnt = 0;
struct pt_ioctl *pti = &pt_ioctl[minor(dev)];
int error = 0;
again:
if ((tp->t_state&TS_ISOPEN) == 0)
goto block;
if (pti->pt_flags & PF_REMOTE) {
if (tp->t_canq.c_cc)
goto block;
while (uio->uio_iovcnt > 0 && tp->t_canq.c_cc < TTYHOG - 1) {
iov = uio->uio_iov;
if (iov->iov_len == 0) {
uio->uio_iovcnt--;
uio->uio_iov++;
continue;
}
if (cc == 0) {
cc = MIN(iov->iov_len, BUFSIZ);
cc = MIN(cc, TTYHOG - 1 - tp->t_canq.c_cc);
cp = locbuf;
error = uiomove(cp, cc, uio);
if (error)
return (error);
/* check again for safety */
if ((tp->t_state&TS_ISOPEN) == 0)
return (EIO);
}
if (cc)
(void) b_to_q(cp, cc, &tp->t_canq);
cc = 0;
}
(void) putc(0, &tp->t_canq);
ttwakeup(tp);
wakeup((caddr_t)&tp->t_canq);
return (0);
}
while (uio->uio_iovcnt > 0) {
iov = uio->uio_iov;
if (cc == 0) {
if (iov->iov_len == 0) {
uio->uio_iovcnt--;
uio->uio_iov++;
continue;
}
cc = MIN(iov->iov_len, BUFSIZ);
cp = locbuf;
error = uiomove(cp, cc, uio);
if (error)
return (error);
/* check again for safety */
if ((tp->t_state&TS_ISOPEN) == 0)
return (EIO);
}
while (cc > 0) {
if ((tp->t_rawq.c_cc + tp->t_canq.c_cc) >= TTYHOG - 2 &&
(tp->t_canq.c_cc > 0 || !(tp->t_iflag&ICANON))) {
wakeup((caddr_t)&tp->t_rawq);
goto block;
}
(*linesw[tp->t_line].l_rint)(*cp++&0377, tp);
cnt++;
cc--;
}
cc = 0;
}
return (0);
block:
/*
* Come here to wait for slave to open, for space
* in outq, or space in rawq.
*/
if ((tp->t_state&TS_CARR_ON) == 0)
return (EIO);
if ((pti->pt_flags & PF_NBIO) || (flag & IO_NDELAY)) {
iov->iov_base -= cc;
iov->iov_len += cc;
uio->uio_resid += cc;
uio->uio_offset -= cc;
if (cnt == 0)
return (EWOULDBLOCK);
return (0);
}
if (ptydebug) printf("SLEEP(2) c_cf %d\n", u.u_procp->p_pid);
sleep((caddr_t)&tp->t_rawq.c_cf, TTOPRI);
goto again;
}
/*ARGSUSED*/
ptyioctl(dev, cmd, data, flag)
caddr_t data;
dev_t dev;
{
register struct tty *tp = &pt_tty[minor(dev)];
register struct pt_ioctl *pti = &pt_ioctl[minor(dev)];
register u_char *cc = tp->t_cc;
int stop, error;
extern ttyinput();
/*
* IF CONTROLLER STTY THEN MUST FLUSH TO PREVENT A HANG.
* ttywflush(tp) will hang if there are characters in the outq.
*/
if (cdevsw[major(dev)].d_open == ptcopen) {
if ((cmd & 0xffff) == (TIOCIOANS(0) & 0xffff)) {
if (!(pti->pt_flags & PF_LIOC) || pti->pt_ioc.c_cc)
return (EINVAL);
(void) b_to_q(data, IOCPARM_LEN(cmd), &pti->pt_ioc);
wakeup((caddr_t)&pti->pt_ioc);
return (0);
}
switch (cmd) {
case TIOCPKT:
if (*(int *)data) {
if (pti->pt_flags & PF_UCNTL)
return (EINVAL);
pti->pt_flags |= PF_PKT;
} else
pti->pt_flags &= ~PF_PKT;
return (0);
case TIOCUCNTL:
if (*(int *)data) {
if (pti->pt_flags & PF_PKT)
return (EINVAL);
pti->pt_flags |= PF_UCNTL;
} else
pti->pt_flags &= ~PF_UCNTL;
return (0);
case TIOCTIOC:
if (*(int *)data) {
if (pti->pt_flags & PF_UCNTL)
return (EINVAL);
pti->pt_flags |= PF_TIOC;
} else {
pti->pt_flags &= ~(PF_TIOC|PF_LIOC|PF_WIOC);
while (pti->pt_ioc.c_cc)
(void) getc(&pti->pt_ioc);
wakeup((caddr_t)&pti->pt_ioc);
}
return (0);
case TIOCBLK:
if (*(int *)data)
pti->pt_flags |= PF_BLOCK;
else {
if (pti->pt_flags & PF_OWAIT)
wakeup((caddr_t)pti + 1);
pti->pt_flags &= ~(PF_BLOCK|PF_OWAIT);
ptswake(tp);
}
return (0);
case TIOCREMOTE:
if (*(int *)data)
pti->pt_flags |= PF_REMOTE;
else
pti->pt_flags &= ~PF_REMOTE;
ttyflush(tp, FREAD|FWRITE);
return (0);
case FIONBIO:
if (*(int *)data)
pti->pt_flags |= PF_NBIO;
else
pti->pt_flags &= ~PF_NBIO;
return (0);
case FIONREAD:
*(int *)data = tp->t_outq.c_cc;
return (0);
case TIOCSETP:
case TIOCSETN:
case TIOCSETD:
case TIOCSETA:
case TIOCSETAW:
case TIOCSETAF:
case JUNK_TIOCSETAS:
case JUNK_TIOCSETAWS:
case JUNK_TIOCSETAFS:
while (getc(&tp->t_outq) >= 0)
;
break;
}
} else if (pti->pt_flags & PF_TIOC) {
while (pti->pt_flags & PF_LIOC) {
pti->pt_flags |= PF_WIOC;
switch (tsleep((caddr_t)&pti->pt_flags,TTIPRI-1,5*hz)) {
case TS_OK:
continue;
case TS_SIG:
case TS_TIME:
return (EBUSY);
}
}
pti->pt_flags |= PF_LIOC | PF_BLOCK;
while (pti->pt_ioc.c_cc)
(void) getc(&pti->pt_ioc);
(void) b_to_q(&cmd, sizeof cmd, &pti->pt_ioc);
if (cmd & IOC_IN)
(void) b_to_q(data, IOCPARM_LEN(cmd), &pti->pt_ioc);
ptcwakeup(tp, FREAD);
switch (tsleep((caddr_t)&pti->pt_ioc, TTIPRI-1, 5*hz)) {
case TS_SIG:
case TS_TIME:
while (pti->pt_ioc.c_cc)
(void) getc(&pti->pt_ioc);
if (pti->pt_flags & PF_WIOC)
wakeup((caddr_t)&pti->pt_flags);
if (pti->pt_flags & PF_OWAIT)
wakeup((caddr_t)pti + 1);
pti->pt_flags &= ~(PF_LIOC|PF_WIOC|PF_BLOCK|PF_OWAIT);
ptswake(tp);
return (EBUSY);
case TS_OK:
break;
}
if (pti->pt_ioc.c_cc == 0) {
if (pti->pt_flags & PF_WIOC)
wakeup((caddr_t)&pti->pt_flags);
if (pti->pt_flags & PF_OWAIT)
wakeup((caddr_t)pti + 1);
pti->pt_flags &= ~(PF_LIOC|PF_WIOC|PF_BLOCK|PF_OWAIT);
ptswake(tp);
goto doioctl;
}
if (q_to_b(&pti->pt_ioc, &error, sizeof error) != sizeof error)
error = EINVAL;
if (error == 0 && cmd & IOC_OUT) {
if (IOCPARM_LEN(cmd) != pti->pt_ioc.c_cc)
error = EINVAL;
else
(void) q_to_b(&pti->pt_ioc, data,
pti->pt_ioc.c_cc);
}
while (pti->pt_ioc.c_cc)
(void) getc(&pti->pt_ioc);
if (pti->pt_flags & PF_WIOC)
wakeup((caddr_t)&pti->pt_flags);
if (pti->pt_flags & PF_OWAIT)
wakeup((caddr_t)pti + 1);
pti->pt_flags &= ~(PF_LIOC|PF_WIOC|PF_BLOCK|PF_OWAIT);
ptswake(tp);
return (error);
}
doioctl:
error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag);
if (error < 0)
error = ttioctl(tp, cmd, data, flag);
/*
* Since we use the tty queues internally,
* pty's can't be switched to disciplines which overwrite
* the queues. We can't tell anything about the discipline
* from here...
*
* Nb: this is not really good enough, the line disc open routine
* may have done anything at all, no guarantees that close
* will fix it. This also has the effect of losing the
* previous discipline, which an error on a TIOCSETD shouldn't
* do... Sometime it should be done via an explicit check
* for TIOCSETD, then check to see what linesw[new_number].l_rint
* really is.
*/
if (linesw[tp->t_line].l_rint != ttyinput) {
(*linesw[tp->t_line].l_close)(tp);
tp->t_line = 0;
(void)(*linesw[tp->t_line].l_open)(dev, tp, flag);
error = ENOTTY;
}
if (error < 0) {
if (pti->pt_flags & PF_UCNTL &&
(cmd & ~0xff) == UIOCCMD(0)) {
if (cmd & 0xff) {
pti->pt_ucntl = (u_char)cmd;
ptcwakeup(tp, FREAD);
}
return (0);
}
error = ENOTTY;
}
stop = (tp->t_iflag & IXON) && CCEQ(cc[VSTOP], CTRL('s'))
&& CCEQ(cc[VSTART], CTRL('q'));
if (pti->pt_flags & PF_NOSTOP) {
if (stop) {
pti->pt_send &= ~TIOCPKT_NOSTOP;
pti->pt_send |= TIOCPKT_DOSTOP;
pti->pt_flags &= ~PF_NOSTOP;
ptcwakeup(tp, FREAD);
}
} else {
if (!stop) {
pti->pt_send &= ~TIOCPKT_DOSTOP;
pti->pt_send |= TIOCPKT_NOSTOP;
pti->pt_flags |= PF_NOSTOP;
ptcwakeup(tp, FREAD);
}
}
return (error);
}
#endif
Continuous source code history from original PDP-7 UNIX to FreeBSD 2, the first fully unencumbered FreeBSD release.